Unreal Engine Issues
Unreal Engine Issues
Crash when casting to owner from AnimGraph
OLD - Anim - Sep 6, 2016Crash occurs when casting back to the pawn owner from the Anim Graph. In this case, it is being used for "Copy Pose from Mesh" Workaround: Cast to Owner from Event Graph, defining variable as the ...
[CrashReport] Crash on Mac related to editor close
UE - Platform - Apple - Jun 6, 2017This is a long-standing Mac crash that occurs with low frequency, but has affected more than 500 users since it started (possibly in the 4.11 release) It has recently been experienced internally by ...
Changing blueprint default values inside arrays only updates loaded child blueprints
UE - CoreTech - Jul 30, 2020The rules for delta serialization in UE4 are complicated, and the editor tries to hide them from you, which works 90% of the time but can lead to confusion and data loss in other situations. In the ...
Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)
UE - Framework - Dec 19, 2025This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...
Race condition in full builds of UE4 engine source
UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 26, 2019This is a race condition caused by how "Clean.bat", a batch file used during rebuilds, tries to manually rebuild the UnrealBuildTool project when it runs. This causes a spam of UnrealBuildTool build ...
Import Source disappears in Textures after loading asynchronously loaded level
UE - Editor - Content Pipeline - Import and Export - Dec 15, 2015It looks like when reimporting a texture asset into the engine after loading a level, you will be confronted with the File Selection box and not the reimport successful notification. In fact if you ...
Crash Re-Importing animation with Additive Layer Tracks after adding a bone to the hierarchy
OLD - Anim - Feb 13, 2017Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 633] Array index out of bounds: 68 from an array of size 68 Source Context: 733 734 Extrac ...
Blueprint improperly marked dirty when it contains a latent node with a byte enum
UE - Framework - Blueprint Editor - Sep 23, 2024In UE 5.4, when deleting actors in our levels, some blueprints will be mark dirty despite not having changed. We traced that down to FAssetRenameManager::CheckPackageForSoftObjectReferences. The af ...
Incorrect config property serialization for UStructs used as TMap keys or contained in a TSet with a single value. Diffs taken from default-value of each member type, instead of from default-value of the struct
UE - CoreTech - Nov 18, 2024Consider a UStruct with some basic type members, each one with a default value specified in the struct. Also consider a TSet or TMap with that struct as keys, used inside a UObject as a UProperty an ...
Event Tick is not running once packaged
UE - Gameplay - Components - Jul 20, 2015Event Tick works when it's running on Windows however once it's packaged or even launched onto all platforms, the event tick does not work as anticipated. This happens on all platforms. *Project ca ...